The influence of rapid influenza diagnostic testing on antibiotic prescribing patterns in rural Thailand

Community pharmacists as antimicrobial resistance stewards: a narrative review on their contributions and challenges in low- and middle-income countries

Antimicrobial resistance (AMR) is a global public health crisis that impedes the therapeutic effectiveness of available antimicrobial agents. Due to the high burden of infectious diseases and limited resources, especially trained healthcare professionals, low- and middle-income countries (LMICs) are particularly susceptible to the detrimental effects of AMR. Sometimes, as the first and last point of contact for patients seeking treatment for infections, community pharmacists can play a pivotal role in the stewardship required for AMR. This review aims to highlight the contributions made by community pharmacists in LMICs as AMR stewards. The review considers the challenges from the perspectives of limited resources, inadequate training, a lack of policies and regulations, and issues related to patient behavior. Community pharmacists in LMICs could optimize their advocacy contributions by focusing on One Health AMR stewardship. Transformational and actionable patient and population-centric antimicrobial stewardship (AMS) is feasible with the synergy of policymakers and other healthcare providers in the implementation of AMS policies and programs that support community pharmacists in their efforts to promote rational antimicrobial use.

The Role of Procalcitonin as an Antimicrobial Stewardship Tool in Patients Hospitalized with Seasonal Influenza

Background: Up to 60% of the antibiotics prescribed to patients hospitalized with seasonal influenza are unnecessary. Procalcitonin (PCT) has the potential as an antimicrobial stewardship program (ASP) tool because it can differentiate between viral and bacterial etiology. We aimed to explore the role of PCT as an ASP tool in hospitalized seasonal influenza patients. Methods: We prospectively included 116 adults with seasonal influenza from two influenza seasons, 2018–2020. All data was obtained from a single clinical setting and analyzed by descriptive statistics and regression models. Results: In regression analyses, we found a positive association of PCT with 30 days mortality and the amount of antibiotics used. Influenza diagnosis was associated with less antibiotic use if the PCT value was low. Patients with a low initial PCT (<0.25 µg/L) had fewer hospital and intensive care unit (ICU) days and fewer positive chest X-rays. PCT had a negative predictive value of 94% for ICU care stay, 98% for 30 days mortality, and 88% for bacterial coinfection. Conclusion: PCT can be a safe rule-out test for bacterial coinfection. Routine PCT use in seasonal influenza patients with an uncertain clinical picture, and rapid influenza PCR testing, may be efficient as ASP tools.

Perceptions of effective policy interventions and strategies to address antibiotic misuse within primary healthcare in India: A qualitative study

Objectives

Antimicrobial resistance poses a major public health threat. Despite Indian retail sector antibiotic consumption per capita increasing by approximately 22% between 2008 and 2016, empirical studies that examine policy or behavioural interventions addressing antibiotic misuse in primary healthcare are scarce. Our study aimed to assess perceptions of interventions and gaps in policy and practice with respect to outpatient antibiotic misuse in India.

Methods

We conducted 23 semi-structured, in-depth interviews with a variety of key informants with diverse backgrounds in academia, non-government organisations, policy, advocacy, pharmacy, medicine and others. Data were charted into a framework matrix and analysed using a hybrid, inductive and deductive thematic analysis. Themes were analysed and organised according to the socio-ecological model at various levels ranging from the individual to the enabling environment.

Results

Key informants largely focused on the importance of adopting a structural perspective to addressing socio-ecological drivers of antibiotic misuse. There was a recognition that educational interventions targeting individual or interpersonal interactions were largely ineffective, and policy interventions should incorporate behavioural nudge interventions, improve the healthcare infrastructure and embrace task shifting to rectify staffing disparities in rural areas.

Conclusions

Prescription behaviour is perceived to be governed by structural issues of access and limitations in public health infrastructure that create an enabling environment for antibiotic overuse. Interventions should move beyond a clinical and individual focus on behaviour change with respect to antimicrobial resistance and aim for structural alignment between existing disease specific programs and between the informal and formal sector of healthcare delivery in India.

Antibiotic use for respiratory syncytial virus in the Middle East: A surveillance study in hospitalized Jordanian children

Introduction

In developing countries where point-of-care testing is limited, providers rely on clinical judgement to discriminate between viral and bacterial respiratory infections. We performed a cross-sectional cohort study of hospitalized Jordanian children to evaluate antibiotic use for respiratory syncytial virus (RSV) infections.

Materials and methods

Admitting diagnoses from a prior viral surveillance cohort of hospitalized Jordanian children were dichotomized into suspected viral-like, non-pulmonary bacterial-like, and pulmonary bacterial-like infection. Stratifying by sex, we performed a polytomous logistic regression adjusting for age, underlying medical condition, maternal education, and region of residence to estimate prevalence odds ratios (PORs) for antibiotic use during hospitalization. Sensitivity and specificity of admission diagnoses and research laboratory results were compared.

Results

Children with a suspected viral-like admission diagnosis, compared to those with suspected non-pulmonary bacterial-like, were 88% and 86% less likely to be administered an empiric/first-line antibiotic (male, aPOR: 0.12; female, aPOR: 0.14; p-value = <0.001). There were slight differences by sex with males having a lower prevalence than females in being administered an expanded coverage antibiotic; but they had a higher prevalence of macrolide administration than males with non-pulmonary bacterial-like infection. Overall, children with RSV had a 34% probability (sensitivity) of being assigned to a suspected viral-like diagnosis; whereas RSV-negative children had a 76% probability (specificity) of being assigned to a suspected pulmonary bacterial-like diagnosis.

Conclusions

Hospitalized children with a suspected viral-like admission diagnosis were less likely to receive an empiric/first-line and expanded coverage antibiotic compared to suspected non-pulmonary and pulmonary infections; however, when evaluating the accuracy of admission diagnosis to RSV-laboratory results there were considerable misclassifications. These results highlight the need for developing antibiotic interventions for Jordan and the rest of the Middle East.

Differences in antibiotic and antiviral use in people with confirmed influenza: a retrospective comparison of rapid influenza PCR and multiplex respiratory virus PCR tests

Background

Influenza is a highly contagious respiratory virus with clinical impacts on patient morbidity, mortality and hospital bed management. The effect of rapid nucleic acid testing (RPCR) in comparison to standard multiplex PCR (MPCR) diagnosis in treatment decisions is unclear. This study aimed to determine whether RPCR influenza testing in comparison to standard MPCR testing was associated with differences in antibiotic and antiviral (oseltamivir) utilisation and hospital length of stay in emergency department and inpatient hospital settings.

Methods

A retrospective cohort study of positive influenza RPCR and MPCR patients was performed utilising data from the 2017 influenza season. Medical records of correlating patient presentations were reviewed for data collection. An analysis of RPCR versus MPCR patient outcomes was performed examining test turnaround time, antibiotic initiation, oseltamivir initiation and hospital length of stay for both emergency department and inpatient hospital stay. Subgroup analysis was performed to assess oseltamivir use in high risk populations for influenza complications. Statistical significance was assessed using Mann-Whitney test for numerical data and Chi-squared test for categorical data. Odds ratio with 95% confidence intervals were calculated where appropriate.

Results

Overall, 122 RPCR and 362 MPCR positive influenza patients were included in this study. Commencement of antibiotics was less frequent in the RPCR than MPCR cohorts (51% vs 67%; p < 0.01, OR 0.52; 95% CI 0.34–0.79). People at high risk of complications from influenza who were tested with the RPCR were more likely to be treated with oseltamivir compared to those tested with the MPCR (76% vs 63%; p = 0.03, OR 1.81; 95% CI 1.07–3.08). Hospital length of stay was not impacted when either test was used in the emergency department and inpatient settings.

Conclusions

These findings suggest utilisation of RPCR testing in influenza management can improve antibiotic stewardship through reduction in antibiotic use and improvement in oseltamivir initiation in those at higher risk of complications. Further research is required to determine other factors that may have influenced hospital length of stay and a cost-benefit analysis should be undertaken to determine the financial impact of the RPCR test.

Point-prevalence survey of outpatient antibiotic prescription at a tertiary medical center in Sri Lanka: opportunities to improve prescribing practices for respiratory illnesses

Background

Inappropriate antibiotic use is linked to the spread of antimicrobial resistance worldwide, but there are limited systemic data on antibiotic utilization in low- and middle-income countries. The purpose of this study was to evaluate the prevalence and patterns of antibiotic prescription in an ambulatory care setting in Sri Lanka.

Methods

This cross-sectional survey was conducted at the Outpatient Department of a public tertiary medical center in Southern Province, Sri Lanka from February to April 2019. Among consecutive outpatients presenting for care, questionnaires were verbally administered to a systematic random sample to capture information about patient demographics, illness characteristics, and visit outcomes. Prescription data were obtained from the outpatient pharmacy’s electronic prescribing system.

Results

Of 409 surveyed patients, 146 (35.7%) were prescribed an antibiotic. The most frequently prescribed agents were amoxicillin (41 patients, 28.1% of antibiotic recipients) and first-generation cephalosporins (38, 26.0%). Respiratory indications were the most common reason for antibiotic use, comprising 69 (47.3%) of all antibiotic prescriptions. Antibiotics were prescribed for 66.1% of patients presenting with cough and 78.8% of those presenting with rhinorrhea or nasal congestion. Among all antibiotic recipients, 6 (4.1%) underwent diagnostic studies.

Conclusions

A high prevalence of antibiotic prescription was observed, in particular for treatment of respiratory conditions. These data support the need for improved antimicrobial stewardship in the Sri Lankan outpatient setting.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05804-6.

Viral Etiology, Clinical Features and Antibiotic Use in Children <5 Years of Age in the Gambia Presenting With Influenza-like Illness

BACKGROUND

Knowledge regarding the prevalence, clinical features and etiology of pediatric influenza-like illness (ILI) remains limited in African settings. Furthermore, it is likely that many children presenting with ILI receive antibiotics unnecessarily. More data are required to develop antimicrobial stewardship practice and guide effective vaccine strategies. We undertook a 1-year prospective study of ILI in the Gambia.

METHODS

Children <5 years of age presenting with ILI from March 2018 to March 2019 were recruited. Clinical and antibiotic prescribing data were collected. Nasopharyngeal swabs were collected and analyzed for 12 respiratory viruses using a multiplex polymerase chain reaction.

RESULTS

From a total of 735 ILI episodes, 530 (72.1%) nasopharyngeal swabs were positive for ≥1 virus. Of these, 36.7% were positive for rhinovirus, 14.7% for respiratory syncytial virus, 8.4% for influenza and 7.2% for human metapneumovirus. Compared with children <6 months of age, influenza was more common in 6- to 23-month-old children [odd ratio (OR): 5.68; 95% confidence interval (CI): 1.72-18.76; P = 0.004]. Respiratory syncytial virus and human metapneumovirus were associated with low peripheral oxygen saturations (OR: 2.13; 95% CI: 1.23-3.69; P = 0.007; and OR: 2.44; 95% CI: 1.13-5.27; P = 0.023, respectively). Antibiotics were prescribed in 78.3% of all ILI cases.

CONCLUSIONS

A broad range of viruses are responsible for pediatric ILI in the Gambia. Refined treatment guidelines, improved diagnostic capacity and vaccines to prevent respiratory viruses will all play a role in reducing antimicrobial use for these cases.

Previously Derived Host Gene Expression Classifiers Identify Bacterial and Viral Etiologies of Acute Febrile Respiratory Illness in a South Asian Population

Background

Pathogen-based diagnostics for acute respiratory infection (ARI) have limited ability to detect etiology of illness. We previously showed that peripheral blood-based host gene expression classifiers accurately identify bacterial and viral ARI in cohorts of European and African descent. We determined classifier performance in a South Asian cohort.

Methods

Patients ≥15 years with fever and respiratory symptoms were enrolled in Sri Lanka. Comprehensive pathogen-based testing was performed. Peripheral blood ribonucleic acid was sequenced and previously developed signatures were applied: a pan-viral classifier (viral vs nonviral) and an ARI classifier (bacterial vs viral vs noninfectious).

Results

Ribonucleic acid sequencing was performed in 79 subjects: 58 viral infections (36 influenza, 22 dengue) and 21 bacterial infections (10 leptospirosis, 11 scrub typhus). The pan-viral classifier had an overall classification accuracy of 95%. The ARI classifier had an overall classification accuracy of 94%, with sensitivity and specificity of 91% and 95%, respectively, for bacterial infection. The sensitivity and specificity of C-reactive protein (>10 mg/L) and procalcitonin (>0.25 ng/mL) for bacterial infection were 100% and 34%, and 100% and 41%, respectively.

Conclusions

Previously derived gene expression classifiers had high predictive accuracy at distinguishing viral and bacterial infection in South Asian patients with ARI caused by typical and atypical pathogens.

Utility of Rapid Influenza Molecular Testing in an Outpatient Hemodialysis Unit: A Prospective Cohort Study

Background:

Early initiation of antiviral therapy for individuals at risk for severe influenza infection is important for improving patient outcomes. Current guidelines recommend empiric antiviral therapy for patients with end-stage kidney disease presenting with suspected influenza infection. Rapid molecular influenza assays may reduce diagnostic uncertainty and improve patient outcomes by providing faster diagnostics compared to traditional batched polymerase chain reaction (PCR) testing.

Objective:

To determine the utility of implementing a rapid influenza PCR assay compared to the standard of care in a hemodialysis unit.

Design:

This is a prospective cohort study.

Setting:

A hospital-based dialysis unit in a tertiary care hospital.

Patients:

Adult patients with end-stage kidney disease on intermittent hemodialysis.

Measurements:

Patient characteristics, influenza PCR swab results, antibiotic prescriptions, antiviral prescriptions, emergency room visits and hospitalizations.

Methods:

From November 1, 2017 to March 31, 2018, we assigned samples collected from a single center, hemodialysis unit to be processed using a rapid influenza PCR (cobas® Influenza A/B & respiratory syncytial virus assay) or the standard of care (in-house developed multiplex PCR). Samples were assigned to the rapid PCR if the patient received dialysis treatment in the morning dialysis shift, while the remainder were processed as per standard of care. Study outcomes included the time from collection to result of nasopharyngeal swab, prescription of influenza antiviral therapy, time to receiving prescription, and the need for emergency department visit or hospitalization within 2 weeks of presentation.

Results:

During the study period, 44 patients were assessed (14 with the rapid PCR and 30 with the standard of care assay). Compared to conventional testing, the time to result was shorter using rapid PCR compared to conventional testing (2.3 vs 22.6 hours, P < .0001). Individuals who were tested using the rapid PCR had a tendency to shorter time to receiving antiviral prescriptions (0.7 days vs 2.1 days, P = .11), and fewer emergency department visits (7.1% vs 30%, P = .13) but no difference in hospitalizations (14.3% vs 30%, P = .46) within 2 weeks of testing.

Limitations:

This is a single center non-randomized study with a relatively small sample size. Patients who were tested using the standard of care assay experienced a delay in the prescription of antiviral therapy which deviates from recommended clinical practice.

Conclusions:

Rapid influenza molecular testing in the hemodialysis unit was associated with a shorter time to a reportable result and with a tendency to reduced time to prescription of antiviral therapy. Rapid molecular testing should be compared with standard of care (empiric therapy) in terms of economic costs, adverse events, and influenza-related outcomes.

Combining Procalcitonin and Rapid Multiplex Respiratory Virus Testing for Antibiotic Stewardship in Older Adult Patients With Severe Acute Respiratory Infection

OBJECTIVES

Virus infection is underevaluated in older adults with severe acute respiratory infections (SARIs). We aimed to evaluate the clinical impact of combining point-of-care molecular viral test and serum procalcitonin (PCT) level for antibiotic stewardship in the emergency department (ED).

DESIGN

A prospective twin-center cohort study was conducted between January 2017 and March 2018.

SETTING AND PARTICIPANTS

Older adult patients who presented to the ED with SARIs received a rapid molecular test for 17 respiratory viruses and a PCT test.

MEASURES

To evaluate the clinical impact, we compared the outcomes of SARI patients between the experimental cohort and a propensity score-matched historical cohort. The primary outcome was the proportion of antibiotics discontinuation or de-escalation in the ED. The secondary outcomes included duration of intravenous antibiotics, length of hospital stay, and mortality.

RESULTS

A total of 676 patients were included, of which 169 patients were in the experimental group and 507 patients were in the control group. More than one-fourth (27.9%) of the patients in the experimental group tested positive for virus. Compared with controls, the experimental group had a significantly higher proportion of antibiotics discontinuation or de-escalation in the ED (26.0% vs 16.1%, P = .007), neuraminidase inhibitor uses (8.9% vs 0.6%, P < .001), and shorter duration of intravenous antibiotics (10.0 vs 14.5 days, P < .001).

CONCLUSIONS AND IMPLICATIONS

Combining rapid viral surveillance and PCT test is a useful strategy for early detection of potential viral epidemics and antibiotic stewardship. Clustered viral respiratory infections in a nursing home is common. Patients transferred from nursing homes to ED may benefit from this approach.

Use of clinical algorithms and rapid influenza testing to manage influenza-like illness: a cost-effectiveness analysis in Sri Lanka

Background

Acute respiratory infections are a common reason for antibiotic overuse. We previously showed that providing Sri Lankan clinicians with positive rapid influenza test results was associated with a reduction in antibiotic prescriptions. The economic impact of influenza diagnostic strategies is unknown.

Methods

We estimated the incremental cost per antibiotic prescription avoided with three diagnostic strategies versus standard care when managing Sri Lankan outpatients with influenza-like illness (ILI): (1) influenza clinical prediction tool, (2) targeted rapid influenza testing and (3) universal rapid influenza testing. We compared findings with literature-based estimates of the cost of antimicrobial resistance attributable to each antibiotic prescription.

Results

Standard care was less expensive than other strategies across all parameter values in one-way sensitivity analyses. The incremental cost per antibiotic prescription avoided with clinical prediction versus standard care was US$3.0, which was lower than the base-case estimate of the cost of antimicrobial resistance per ILI antibiotic prescription (US$12.5). The incremental cost per antibiotic prescription avoided with targeted testing and universal testing versus standard care were both higher than the base-case cost of antimicrobial resistance per ILI antibiotic prescription: US$49.1 and US$138.3, respectively. To obtain a cost-effectiveness ratio lower than US$12.5 with targeted testing versus standard care, the test price must be <US$2.6. At a higher threshold of US$28.7, the test price must be <US$7.7.

Conclusion

Clinical prediction tools and targeted rapid influenza testing may be cost-saving strategies in Sri Lanka when accounting for the societal cost of antimicrobial resistance.

Interventions to Reduce Antibiotic Prescribing in LMICs: A Scoping Review of Evidence from Human and Animal Health Systems

This review identifies evidence on supply-side interventions to change the practices of antibiotic prescribers and gatekeepers in low- and middle-income countries (LMICs). A total of 102 studies met the inclusion criteria, of which 70 studies evaluated interventions and 32 provided insight into prescribing contexts. All intervention studies were from human healthcare settings, none were from animal health. Only one context study examined antibiotic use in animal health. The evidence base is uneven, with the strongest evidence on knowledge and stewardship interventions. The review found that multiplex interventions that combine different strategies to influence behaviour tend to have a higher success rate than interventions based on single strategies. Evidence on prescribing contexts highlights interacting influences including health system quality, education, perceptions of patient demand, bureaucratic processes, profit, competition, and cultures of care. Most interventions took place within one health setting. Very few studies targeted interventions across different kinds of providers and settings. Interventions in hospitals were the most commonly evaluated. There is much less evidence on private and informal private providers who play a major role in drug distribution in LMICs. There were no interventions involving drug detailers or the pharmaceutical companies despite their prominent role in the contextual studies.

Health care costs of influenza-related episodes in high income countries: A systematic review

Introduction

This study systematically reviews costing studies of seasonal influenza-like illness (ILI) in high-income countries. Existing reviews on the economic impact of ILI do not report information on drug consumption and its costs, nor do they provide data on the overall cost per episode.

Methods

The PRISMA-P checklist was used to design the research protocol. Studies included were cost of illness analysis (COI) and modeling studies that estimated the cost of ILI episodes. Records were searched from January 2000 to December 2016 in electronic bibliographic databases including Medline, Embase, Science Direct, the Cochrane Library, the Centre for Reviews and Disseminations of the University of York, and Google scholar. References from the included studies were hand-searched for completion. Abstract screening, full-text analysis and data extraction were performed by two reviewers independently and discrepancies were resolved by discussion with a third reviewer. A standardized, pre-piloted form was used for data extraction. All costs were converted to 2015 US$ Purchasing Power Parities.

Results

The literature search identified 5,104 records. After abstract and title screening, 76 studies were analyzed full-text and 27 studies were finally included in the review. Full estimates of the cost per episode range from US$19 in Korea to US$323 in Germany. Particularly, the cost per episode of laboratory confirmed influenza cases was estimated between US$64 and US$73. Inpatient and outpatient services account for the majority of the costs. Differences in the estimates may reflect country-specific characteristics, as well as other study-specific features including study design, identification strategy of ILI cases, study populations and types of costs included in the analysis. Children usually register higher costs, whereas evidence for the elderly is less conclusive. Patients risk-profile, co-morbidities and complications are the other important cost-drivers. None of the papers considered appropriateness in resource use (e.g. abuse of antibiotics). Despite cost of illness studies have ultimately a descriptive role, evidence on (in)appropriateness is useful for policy-makers.

Systematic review of the impact of point-of-care testing for influenza on the outcomes of patients with acute respiratory tract infection

Acute respiratory tract infections are a major cause of morbidity and mortality and represent a significant burden on the health care system. Laboratory testing is required to definitively distinguish infecting influenza virus from other pathogens, resulting in prolonged emergency department (ED) visits and unnecessary antibiotic use. Recently available rapid point-of-care tests (POCT) may allow for appropriate use of antiviral and antibiotic treatments and decrease patient lengths of stay. We undertook a systematic review to assess the effect of POCT for influenza on three outcomes: (1) antiviral prescription, (2) antibiotic prescription, and (3) patient length of stay in the ED. The databases Medline and Embase were searched using MeSH terms and keywords for influenza, POCT, antivirals, antibiotics, and length of stay. Amongst 245 studies screened, 30 were included. The majority of papers reporting on antiviral prescription found that a positive POCT result significantly increased use of antivirals for influenza compared with negative POCT results and standard supportive care. A positive POCT result also led to decreased antibiotic use. The results of studies assessing the effect of POCT on ED length of stay were not definitive. The studies assessed in this systematic review support the use of POCT for diagnosis of influenza in patients suffering an acute respiratory infection. Diagnosis using POCT may lead to more appropriate prescription of treatments for infectious agents. Further studies are needed to assess the effect of POCT on the length of stay in ED.

The impact of commercial rapid respiratory virus diagnostic tests on patient outcomes and health system utilization

INTRODUCTION

Acute respiratory tract infections due to influenza A/B and respiratory syncytial virus (RSV) are major causes of morbidity and mortality globally. Rapid tests for detection of these pathogens include antigen detection point of care tests (POC) and newer easy to use molecular tests. From experience, these assays improve both laboratory workflow and assay interpretation issues. However, the question of the benefits of using rapid test technology compared to routine laboratory testing for respiratory viral pathogens is still often asked. Areas covered: Specifically, this review aims to; 1) identify clinical/patient indicators that can be measured prior to and following the implementation of rapid diagnostic test for influenza and RSV, 2) provide multiple perspectives on the extent of impact of a rapid diagnostic test, including direct and indirect outcomes, and 3) identify the technological advancements in the development of rapid testing, demonstrating a timeline that transitions from antigen-based assays to molecular assays. Expert commentary: Key benefits to the use of either antigen-based or molecular rapid tests for patient care, patient flow within institutions, as well as laboratory utilization are identified. Due to improved test characteristics, the authors feel that rapid molecular tests have greater benefits than antigen-based detection methods.

Use of Rapid Influenza Testing to Reduce Antibiotic Prescriptions Among Outpatients with Influenza-Like Illness in Southern Sri Lanka

Acute respiratory tract infections (ARTIs) are a common reason for unnecessary antibiotic prescriptions worldwide. Our objective was to determine if providing access to rapid influenza test results could reduce antibiotic prescriptions for ARTIs in a resource-limited setting. We conducted a prospective, pre-post study from March 2013 to October 2014. Outpatients presenting to a hospital in Sri Lanka were surveyed for influenza-like illness-onset of fever ≥ 38.0°C and cough in prior 7 days. Enrolled patients were administered a structured questionnaire, physical examination, and nasal/nasopharyngeal sampling for rapid influenza A/B testing. Influenza test results were released only during phase 2 (January-October 2014). We enrolled 571 patients with ILI-316 in phase 1 and 241 in phase 2. The proportion positive for influenza was 46.5% in phase 1 and 28.6% in phase 2, P < 0.001. Between phases, antibiotic prescriptions decreased from 81.3% to 69.3% (P = 0.001) among all patients and from 83.7% to 62.3% (P = 0.001) among influenza-positive patients. On multivariable analysis, a positive influenza result during phase 2 was associated with lower odds of antibiotic prescriptions (OR = 0.50, 95% CI = 0.26-0.95). This prospective study suggests that providing access to rapid influenza testing may reduce unnecessary antibiotic prescriptions in resource-limited settings.

An under-recognized influenza epidemic identified by rapid influenza testing, southern Sri Lanka, 2013

Influenza accounts for a large burden of acute respiratory tract infections in high-income countries; data from lower-income settings are limited due to lack of confirmatory testing. Consecutive outpatients presenting to the largest tertiary care hospital in southern Sri Lanka were surveyed for influenza-like illness (ILI), defined as acute onset of fever ≥ 38.0°C and cough. Patients were administered a questionnaire and nasal/nasopharyngeal sampling for rapid influenza A/B testing. We enrolled 311 patients with ILI from March to November 2013: 170 (54.7%) children and 172 (55.3%) males. Approximately half (147, 47.3%) tested positive for influenza, but 253 (81.4%) were prescribed antibiotics. On bivariable analysis, symptoms associated with influenza included pain with breathing (P < 0.001), headache (P = 0.005), fatigue (P = 0.003), arthralgias (P = 0.003), and myalgias (P = 0.006) in children and pain with breathing (P = 0.01), vomiting (P = 0.03), and arthralgias (P = 0.03) in adults. Our final clinical predictive models had low sensitivity and fair specificity-50.0% (95% CI: 38.6-61.4%) and 83.2% (95% CI: 73.4-90.0%), respectively, in children and 52.2% (95% CI: 39.9-64.2%) and 81.4% (95% CI: 70.0-89.4%), respectively, in adults. Our study confirms the ability of rapid influenza testing to identify an influenza epidemic in a setting in which testing is not routinely available.

The Enigma ML FluAB-RSV assay: a fully automated molecular test for the rapid detection of influenza A, B and respiratory syncytial viruses in respiratory specimens

The Enigma(®) ML FluAB-RSV assay (Enigma Diagnostics, Porton Down, Salisbury, UK) is a CE-IVD marked multiplex molecular panel for the detection of influenza A, B and respiratory syncytial viruses in nasopharyngeal swabs. The assay runs on the fully automated Enigma ML platform without further specimen manipulation and provides a sample-to-answer result within 95 min. The reported sensitivity and specificity for influenza A are 100% (95% CI: 98.2-100) and 98.3% (95% CI: 95.5-99.4), respectively, for influenza B are 100% (95% CI: 98.2-100) and 98.7% (95% CI: 96-99.6), respectively, and for respiratory syncytial virus are 100% (95% CI: 98.2-100) and 99.4% (95% CI: 97.2-99.9), respectively.

Clinical relevance of rhinovirus infections among adult hospitalized patients

Human rhinovirus (HRV) is an emerging viral pathogen.

Aim

To characterize a group of patients admitted due to infection by this agent in a general hospital in Chile.

Methods

Cases were identified by RT-PCR for 1 year through active surveillance of patients admitted with severe respiratory illness. Diagnosis was not available during hospitalization. Thirty-two cases were identified, 90% were ≥60 years old or had co-morbid conditions. Human rhinovirus-related admissions represented 23.7% of hospitalization due to severe acute respiratory infections among adults and ranked second to influenza (37.8%). Patients presented with pneumonia (68.8%), decompensated chronic lung conditions (21.9%), heart failure or influenza-like illness (6.3% each). Admission to intensive or intermediate care units was required by 31.2% and in-hospital mortality reached 12.5%. A CURB-65 score ≥3 was significantly associated to in-hospital mortality (p < 0.05). Most patients received antibiotics (90%).

Conclusions

Human rhinovirus infections in elderly patients with co-morbid conditions are associated with hospitalizations, requiring critical or semi-critical antibiotics use. A high CURB-65 score was associated to in-hospital mortality.

Better tests, better care: improved diagnostics for infectious diseases

In this IDSA policy paper, we review the current diagnostic landscape, including unmet needs and emerging technologies, and assess the challenges to the development and clinical integration of improved tests. To fulfill the promise of emerging diagnostics, IDSA presents recommendations that address a host of identified barriers. Achieving these goals will require the engagement and coordination of a number of stakeholders, including Congress, funding and regulatory bodies, public health agencies, the diagnostics industry, healthcare systems, professional societies, and individual clinicians.

Antibiotics Smart Use: a workable model for promoting the rational use of medicines in Thailand

The Antibiotics Smart Use (ASU) programme was introduced in Thailand as a model to promote the rational use of medicines, starting with antibiotics. The programme's first phase consisted of assessing interventions intended to change prescribing practices; the second phase examined the feasibility of programme scale-up. Currently the programme is in its third phase, which centres on sustainability. This paper describes the concept behind ASU, the programme's functional modalities, the development of its conceptual framework and the implementation of its first and second phases. To change antibiotic prescription practices, multifaceted interventions at the individual and organizational levels were implemented; to maintain behaviour change and scale up the programme, interventions at the network and policy levels were used. The National Health Security Office has adopted ASU as a pay-for-performance criterion, a major achievement that has led to the programme's expansion nationwide. Despite limited resources, programme scale-up and sustainability have been facilitated by the promotion of local ownership and mutual recognition, which have generated pride and commitment. ASU is clearly a workable entry point for efforts to rationalize the use of medicines in Thailand. Its long-term sustainability will require continued local commitment and political support, effective auditing and integration of ASU into routine systems with appropriate financial incentives.

Short report: Rapid-test based identification of influenza as an etiology of acute febrile illness in Cambodia

Influenza can be manifested as an acute febrile illness, with symptoms similar to many pathogens endemic to Cambodia. The objective of this study was to evaluate the Quickvue influenza A+B rapid test to identify the etiology of acute febrile illness in Cambodia. During December 2006–May 2008, patients enrolled in a study to identify the etiology of acute febrile illnesses were tested for influenza by real-time reverse transcriptase PCR (RT-PCR) and Quickvue influenza A+B rapid test. The prevalence of influenza was 19.7% by RT-PCR. Compared with RT-PCR, the sensitivity and specificity of the rapid test were 52.1% and 92.5%, respectively. The influenza rapid test identified the etiology in 10.2% of enrollees and ≥ 35% during peak times of influenza activity. This study suggests that rapid influenza tests may be useful during peak times of influenza activity in an area where several different etiologies can present as an acute febrile illness.

Sensitivity and specificity of rapid influenza testing of children in a community setting

Please cite this paper as: Stebbins et al. (2011) Sensitivity and specificity of rapid influenza testing of children in a community setting. Influenza and Other Respiratory Viruses 5(2), 104–109.

Introduction  Rapid influenza testing (RFT) allows for a rapid point‐of‐care diagnosis of influenza. The Quidel QuickVue^® Influenza A+B test (QuickVue) has a reported manufacturer’s sensitivity and specificity of 73% and 96%, respectively, with nasal swabs. However, investigators have shown sensitivities ranging from 22% to 77% in community settings.

Methods  The QuickVue rapid influenza test was evaluated in a population of elementary (K‐5) school children, using testing in the home, as part of the Pittsburgh Influenza Prevention Project during the 2007–2008 influenza season. The QuickVue test was performed with nasal swab in full accordance with package instructions and compared with the results of nasal swab semi‐quantitative RT‐PCR.

Results  Sensitivity of the QuickVue was found to be 27% in this sample. There was no statistically valid correlation between the semi‐quantitative PCR result and the QuickVue result.

Conclusions  This study is consistent with the low sensitivity of the QuickVue test also reported by others. Viral load, technique, and the use of nasal swabs were examined as contributing factors but were not found to be explanations for this result. Community testing includes patients who are on the lower spectrum of illness which would not be the case in hospital or clinic samples. This suggests that RFT is less sensitive for patients at the lower spectrum of illness, with less severe disease.

Comparison of 10 indirect fluorescent antibodies to detect and type influenza A specimens

CONTEXT

Management of influenza infections relies on rapid, accurate, and sensitive diagnostic techniques. Influenza A (IA) strain typing has become more important since the emergence of highly pathogenic avian and novel influenza strains and the high frequency of oseltamivir resistance in circulating H1N1 isolates.

OBJECTIVE

To analyze the performance of indirect fluorescent antibody testing for subtyping a broad range of IA strains.

DESIGN

Ten indirect fluorescent antibody reagents were used to detect and type 100 archived IA respiratory specimens from 1986 through 1995 and 2006 through 2007 and a reassortant, nonpathogenic H5N1 sample. Both direct specimen and cultured isolates were tested. Reverse transcription-polymerase chain reaction was used to confirm indirect fluorescent antibody results. Three H1N1-, 2 H3N2-, and 1 H1-H2-H3-H5-specific antibodies (Chemicon Diagnostics), an IA pool reagent (Trinity Biotech), and H1, H3, and H1-H3-specific antibodies (Centers for Disease Control and Prevention) were used.

RESULTS

Reverse transcription-polymerase chain reaction confirmed all 100 isolates as IA and identified 71 as H1, 22 as H3, and 7 as non-H1-H3. Sensitivity of direct specimen testing ranged was 18.3% to 57.7% for the H1 reagents, 36.4% to 50.0% for the H3 reagents, and 40.0% to 53.8% for the pool reagents. Subtyping was more sensitive on cultured isolates than direct specimens. Specificity for all antibodies was 89.7% to 100%. The H5N1 sample was positive by direct testing and culture (reverse transcription-polymerase chain reaction, Centers for Disease Control and Prevention H5N1 pool, Chemicon H1-H2-H3-H5). No cross-reactivity was observed when the 10 antibodies were tested against other common respiratory viruses.

CONCLUSIONS

When positive, IA subtyping antibodies can serve as a useful diagnostic tool when multiple influenza virus subtypes are cocirculating with different susceptibility patterns.

Rapid diagnostic testing for seasonal influenza: an evidence-based review and comparison with unaided clinical diagnosis

BACKGROUND

Worldwide, seasonal influenza imposes a considerable health and economic burden. Clinical diagnosis of influenza-like illness (ILI) is complicated by non-specific symptomatology. Rapid flu tests (RFTs) impact treatment decisions and may improve patient care; yet, recommendations for RFT use are broad, and the performance of unaided clinical diagnosis relative to RFTs is unclear.

OBJECTIVES

To determine age-stratified, overall sensitivities and specificities of the widely studied RFT, QuickVue® (Quidel Corporation, San Diego, CA), and clinical diagnosis of ILI by meta-analysis and to seek factors associated with poorer clinical diagnostic discrimination.

METHODS

A systematic literature review was conducted using article selection criteria identifying studies indexed in PubMed/MEDLINE, the Cochrane Library, and other pertinent sources of studies reporting sensitivity, specificity, and effects of RFTs and clinical diagnosis on decision-making for patients with ILI.

RESULTS

QuickVue's® diagnostic specificity exceeds that of unaided clinical diagnosis by 29-31%. False-positive results occur approximately 8.2 times more frequently by unaided clinical diagnosis than by the RFT alone. These findings were unaffected by seasonal variations in disease prevalence. RFTs reduce diagnostic testing, antibiotic use, and emergency department utilization while increasing antiviral prescription rates. No systematic relationship between the broadness of clinical diagnostic criteria for influenza and diagnostic performance was observed across studies included in this review.

CONCLUSIONS

Use of RFTs improves seasonal influenza diagnostic specificity above that based on unaided clinical diagnosis irrespective of the broadness of clinical diagnostic criteria, and affects clinical decision-making. These results provide an improved framework upon which to diagnose influenza, design future RFT studies, and modify existing recommendations for improved ILI patient management.

Factors affecting QuickVue Influenza A + B rapid test performance in the community setting

Rapid diagnosis of influenza can facilitate timely clinical management. We evaluated the performance of the QuickVue Influenza A + B test (Quidel, San Diego, CA) in a community setting and investigated the factors affecting test sensitivity. We recruited 1008 subjects from 30 outpatient clinics in Hong Kong between February and September 2007. Each subject provided 2 pooled pairs of nose and throat swabs; 1 pair was tested by the QuickVue rapid test on site, and the other pair was sent to a laboratory for reference tests. Among 998 enrolled subjects with valid results, the rapid test had overall sensitivity of 0.68 and specificity of 0.96 compared with viral culture. Sensitivity for both influenza A and B was significantly higher for specimens with viral loads greater than 5 log(10) copies/mL. The QuickVue Influenza A + B test has similar sensitivity in point-of-care community settings to more controlled conditions.

The effect of rapid diagnostic testing for influenza on the reduction of antibiotic use in paediatric emergency department

AIM

To determine the influence of rapid diagnosis of influenza on antibiotic prescribing to children presenting with influenza-like illness in the emergency department in a inner city hospital in Istanbul, Turkey.

METHODS

Patients aged 3 to 14 years presenting to an urban children's teaching hospital emergency department were screened for fever and cough, coryza, myalgias and/or malaise. After obtaining informed consent, patients were allocated into two groups. Group 1: patients were prescribed antibiotics after only physical examination; or Group 2: patients were prescribed antibiotics after rapid influenza testing. Nasopharyngeal swabs obtained from all patients were immediately tested in a single-blind manner with Influenza A/B Rapid Test(R) for influenza A and B.

RESULTS

A total of 97 patients were enrolled, and 33 (34%) of these tested positive for influenza. Although frequency of positive results for influenza between the groups was similar (36% vs 32%, respectively), patients in Group 2 were less likely to be prescribed antibiotics when compared to those in Group 1 (32% vs 100%, respectively, p < 0.0001).

CONCLUSION

Rapid diagnosis of influenza in the paediatric emergency department may allow a significant reduction in the over-prescription of antibiotics.

Influenza-associated hospitalization in urban Thai children

BACKGROUND

Studies in North America and Europe have shown that young children are at increased risk of serious complications and hospitalization from influenza infection. In Thailand, however, influenza is commonly considered a mild infection that rarely requires hospitalization. An improved understanding of the burden of serious complications from influenza infection in young children is needed to inform clinical treatment and vaccination guidelines.

METHODS

We conducted a prospective study of children 0-5 years of age with lower respiratory tract infection or influenza-like illness admitted to a pediatric tertiary-care hospital in Bangkok, Thailand during July 2004 to July 2005. All respiratory specimens were tested for influenza using a rapid antigen test and tissue cell culture.

RESULTS

Thirty-nine of 456 (8.6%) hospitalized children had culture-positive influenza. Eighty percent of hospitalized influenza patients had no underlying chronic illnesses. Nineteen (49%) influenza patients required hospital stays of 5 days or more and two patients required mechanical ventilation. Influenza activity demonstrated bimodal seasonal variation with peak activity from August to October and January to April. Cough was present in 38 (97%) cases and fever >38.5 degrees C was significantly associated with influenza.

CONCLUSION

Influenza is an important cause of hospitalization in children <5 years of age in Thailand. Children <5 years should be considered as a target group when establishing clinical guidelines for antiviral treatment and influenza vaccination.

Use of rapid tests and antiviral medications for influenza among primary care providers in the United States

Limited data are available about how physicians diagnose and treat influenza. We conducted an internet-based survey of primary care and emergency physicians to evaluate the use of influenza testing and antiviral medications for diagnosis and treatment of influenza. In April 2005, an electronic link to a 33-question, web-based survey was emailed to members of the American College of Physicians, American Academy of Pediatrics, American Academy of Family Physicians, and American College of Emergency Physicians. Of the 157,674 physician members of the four medical societies, 2649 surveys were completed (1.7%). The majority of participants were internists (59%). Sixty percent of respondents reported using rapid tests to diagnose influenza. Factors associated with using rapid influenza tests included physician specialty, type of patient insurance, and practice setting. After controlling for insurance and community setting, emergency physicians and pediatricians were more likely to use rapid influenza tests than internists [odds ratio (OR) 3.7, confidence interval (CI): 2.3-6.1; and OR 1.7, CI: 1.4-2.1, respectively]. Eighty-six percent of respondents reported prescribing influenza antiviral medications. Reasons for not prescribing antivirals included: patients do not usually present for clinical care within 48 hours of symptom onset (53.0%), cost of antivirals (42.6%) and skepticism about antiviral drug effectiveness (21.7%). The use of rapid tests and antiviral medications for influenza varied by medical specialty. Educating physicians about the utility and limitations of rapid influenza tests and antivirals, and educating patients about seeking prompt medical care for influenza-like illness during influenza season could lead to more rapid diagnosis and improved management of influenza.

Early diagnosis of lower respiratory tract infections (point-of-care tests)

PURPOSE OF REVIEW

Respiratory tract infections are a common reason for prescribing antibiotics, although not all of these infections require such therapy. Rapid diagnosis of etiology using point-of-care tests is a potentially useful way of reducing prescriptions of both unnecessary and unnecessarily broad-spectrum antibiotics. This can also lead to the facilitation of appropriate infection control measures to prevent spread of respiratory viruses within institutions.

RECENT FINDINGS

Point-of-care tests are available for diagnosing influenza, respiratory syncytial virus, Streptococcus pneumoniae, and Legionella infections using easily obtainable specimens. Their main benefit is that results can be obtained in about 15 min with reasonable accuracy. In many situations, however, it is still important to confirm diagnosis with more accurate but slower tests such as bacterial cultures with antibacterial susceptibility testing or viral polymerase chain reaction testing.

SUMMARY

Although the sensitivities of many of the rapid diagnostic tests are moderate, when used at the time of initial consultation, they have the potential to reduce costs, length of stay, secondary spread of respiratory viruses, and inappropriate antibiotic prescribing.